Charles davy



. 0.1)4VY, v GEAR FOR CONTROLLING THE SPEED OF PUMPING ENGINES. No. 447,146. Patented Feb. 24,1891.

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UNITED STATES PATENT OFFICE.

CHARLES DAVY, OF SHEFFIELD, ENGLAND.

GEAR FOR CONTROLLING THE SPEED OF PUMPING-ENGINES.

SPECIFICATION forming part of Letters Patent No. 447,146, dated February 24, 1891.

Application filed May 3, 1390- Serial No. 350,464. (No model.)

To all whom it may concern.-

Be it known that I, CHARLES DAVY, engineer, of WVhitworth Road, Ranmoor, Sheffield, in the county of York, England, have invented new and useful Improved Governing- Gearsrfor the Pumping-Engines of Hydraulic, Forging, or'other Presses, of which the following is a full, clear, and exact description.

My invention relates to improved gear for controlling the speed of the pn mping-engines of a hydraulic press for forging or other purposes where the water is pumped against a variable resistanceas, for instance, directly from the pumping-engines into the cylinders of the press(as distinguished from the employment of a dead-weight accumulator,) and such gear is particularly designed for use in substitution for the so-called hunting-gear described in the specification of a previous patent granted to me, dated the 15th day of December, 1885, No. 332,594.

The primary object of this improved governing-gear is to prevent the running away of the pumping-engines under any conditions of the load.

The governing-gear is such that the quantity of steam supplied is to a certain extent dependent on the resistance to be overcome and the speed at which it is desired that the pumping-engines shall run under the different conditions of working, the effect of the governing-gear being that when the presshead is being depressed against a forging offering little resistance the supply of steam is limited according to the speed at which it is then desired the pumping-engines shall run, and as the resistance increases the steamvalve of the pumping-engine can be opened wider to admit more steam, so that only enough steam can at any time be supplied to run the engines at any predetermined speed,

which cannot be exceeded whatever may be the resistance, if any, to overcome. The extent to which the steam-valve can be opened may be so as to cause the engines to run at an approximately uniform speed, whether the engines be pumping against a low or a high resistance, or thesteam-valvemaybeopened in a less proportion than the increase of the resistance, so that the speed of the engines diminishes as the load increases. For example, when the resistance to'be overcome is small the enginesmay run at, say, one hundred revolutions per minute and at fifty revolutions per minute when the maximum hydraulic pressure is required.

The invention consists, essentially, in the combination, with the steam-valve, of a plunger constantly'acted on in one direction by the hydraulic pressure,- if any, existing in the delivery-pipe of the pumps, and in the other direction by a spring, the position of the plunger under these opposing forces determining the extent to which the steam-valve can be opened.

Reference is to be had to the accompanying drawing, forming part of this specification, wherein I have represented in sectional elevation an example of my improved governinggear.

A is the plunger, working in a case B, in

constantly-open communication by a pipe 0 with the delivery-pipe of the steam-pumping engines.

D is the spring acting on the plunger in opposition to the hydraulic pressure in the case B, and E is the steam-valve to be controlled. The connection of the plunger with thevalve is through the mediumof a hand-lever F, and of a connecting-rod G, adjustably connected to the slotted arm of an L-shaped lever H, the hand-lever F being pivoted on a fixed ful crum at f, and passing through a slot aim the head of the plunger A, the length and position of the slot a being such that at starting the hand-lever is capable of a limited motion (independently of the plunger A) sufficient for opening the steam-valve to the proper extent for running the pumping-engine at the de sired speed when working against a light loadthat is to say, before the pumps have generated any hydraulic pressure, this initial opening of the valve being limited by the lever coming against a stop g, formed by the 7 end of the slot d. Then the pumping-engine is working against the resistance of the forging, the hydraulic pressure increases in the case B, the plunger A is moved out against the pressure of the spring D, and the handlever F is then capable of afurther motion in the same direction for opening the steamvalve to a greater extent, such further motion of the lever being produced by the hand of the attendant following up the movement of the plunger. The length of the slot a in the other direction is such that the hand-lever F maybe moved in the direction for closing the steam-valve E, whatever may be the position of the plunger A, so that the steam may at any time be cut oil: entirely by the valve E acting as a stop-valve.

It will be evident that the speed at which the engines will run may be varied by var ing the effective length or range of the spring D or by changing it for another of diiferent strength. It will also be evident that the valve E, instead of being a double-beat valve, as illustrated, might be a rotary valve, corresponding ports being'provided in the valve and its seat, and the valve-spindle having a short lever-arm, to which the hydraulic ram is connected, as before. My invention' is therefore not limited to the particular form of steam-valve employed.

Having now particularly described and as certained the nature of the said invention and in What manner the same is to be performed, I declare that what I claim is In hydraulic-press pumping-engines, the combination, with a steam-regulating valve, of a plunger acted on in one direction by the hydraulic pressure opposed to the pumpingengines and in the other direction by a spring, and a hand-lever connected to the valve and working in a slot in the plunger, whereby the opening of the valve beyond a certain point is dependent on the position of the plunger and the movement of the hand lever by the attendant, while the valve may be closed independently of the position of the plunger, substantially as specified.

The foregoing specification of my improved governing-gear for the pumping-engines of a hydraulic forging or other press signed by me this 17th day of April, 1890.

, CHARLES DAVY. Witnesses,-

O. 13. 110131318, HENRY F. I[. MARSDEN, Clerks to .Hessrs. Bwrdekm & 00., Solicitors,

41 Nmfolk Street, Sheffield. 

